Trial Outcomes & Findings for Screening for Ovarian Cancer in Older Patients (PLCO Screening Trial) (NCT NCT01696994)

NCT ID: NCT01696994

Last Updated: 2025-07-23

Results Overview

Ovarian cancer deaths confirmed in participants by a death review committee if available, otherwise by death certificate.

• Recruitment status: ACTIVE_NOT_RECRUITING
• Study phase: NA
• Target enrollment: 78216 participants
• Primary outcome timeframe: Events through 13 years of follow-up or through December 31, 2009; median follow-up 11.9 years.
• Results posted on: 2025-07-23

Participant Flow

Participants were enrolled between November 1993 and July 2001 at 10 study centers.

Participants signed a study informed consent prior to being randomized to a study arm.

Participant milestones

Measure	Control Participants receive standard medical care.	Ovarian Screening Participants undergo blood sample collection for CA-125 analysis at baseline annually for 5 years. Participants also undergo an OVR (discontinued in December 1998) and TVU at baseline and annually for 3 years.
Overall Study STARTED	39111	39105
Overall Study COMPLETED	33919	30668
Overall Study NOT COMPLETED	5192	8437

Reasons for withdrawal

Measure	Control Participants receive standard medical care.	Ovarian Screening Participants undergo blood sample collection for CA-125 analysis at baseline annually for 5 years. Participants also undergo an OVR (discontinued in December 1998) and TVU at baseline and annually for 3 years.
Overall Study Cancer Before Rand. (Ovarian Screening)	0	2
Overall Study Died Before Randomization	1	2
Overall Study Died Before ASU (Control)	73	0
Overall Study No Ovaries at Baseline	4807	4851
Overall Study Refused ASU (Control)	311	0
Overall Study Refused Screen (Ovarian Screening)	0	3582

Baseline Characteristics

Screening for Ovarian Cancer in Older Patients (PLCO Screening Trial)

Baseline characteristics by cohort

Measure	Control n=39111 Participants Participants receive standard medical care. Participants complete a baseline questionnaire (BQ) at entry and a dietary history questionnaire (DHQ) during study years 0-6.	Ovarian Screening n=39105 Participants Participants undergo blood sample collection for Cancer Antigen 125 (CA-125) analysis at baseline and annually for 5 years. Participants also undergo an OVR (discontinued in December 1998) and TVU at baseline and annually for 3 years.	Total n=78216 Participants Total of all reporting groups
Age, Categorical <=18 years	0 Participants n=5 Participants	0 Participants n=7 Participants	0 Participants n=5 Participants
Age, Categorical Between 18 and 65 years	25222 Participants n=5 Participants	25233 Participants n=7 Participants	50455 Participants n=5 Participants
Age, Categorical >=65 years	13889 Participants n=5 Participants	13872 Participants n=7 Participants	27761 Participants n=5 Participants
Age, Continuous	62.5 years STANDARD_DEVIATION 5.4 • n=5 Participants	62.5 years STANDARD_DEVIATION 5.4 • n=7 Participants	62.5 years STANDARD_DEVIATION 5.4 • n=5 Participants
Sex: Female, Male Female	39111 Participants n=5 Participants	39105 Participants n=7 Participants	78216 Participants n=5 Participants
Sex: Female, Male Male	0 Participants n=5 Participants	0 Participants n=7 Participants	0 Participants n=5 Participants
Region of Enrollment United States	39111 participants n=5 Participants	39105 participants n=7 Participants	78216 participants n=5 Participants

PRIMARY outcome

Timeframe: Events through 13 years of follow-up or through December 31, 2009; median follow-up 11.9 years.

Ovarian cancer deaths confirmed in participants by a death review committee if available, otherwise by death certificate.

Outcome measures

Measure	Control n=34304 Participants Participants receive standard medical care.	Ovarian Screening n=34253 Participants Participants undergo blood sample collection for CA-125 analysis at baseline annually for 5 years. Participants also undergo an OVR (discontinued in December 1998) and TVU at baseline and annually for 3 years.
Ovarian Cancer Deaths (Including Primary Peritoneal and Fallopian Tube Cancers)	100 Participants	188 Participants

PRIMARY outcome

Timeframe: Events through 13 years of follow-up or through December 31, 2009; median follow-up 11.9 years.

Population: Female participants, excluding females without ovaries at baseline, were analyzed. An intention-to-treat analysis was performed.

Ovarian cancer deaths confirmed in participants by a death review committee if available, otherwise by death certificate. Rate is the number of deaths divided by person years of follow-up in the study.

Outcome measures

Measure	Control n=34304 Participants Participants receive standard medical care.	Ovarian Screening n=34253 Participants Participants undergo blood sample collection for CA-125 analysis at baseline annually for 5 years. Participants also undergo an OVR (discontinued in December 1998) and TVU at baseline and annually for 3 years.
Ovarian Cancer Death Rates (Including Primary Peritoneal and Fallopian Tube Cancers)	2.6 Deaths per 10,000 PY	3.1 Deaths per 10,000 PY

SECONDARY outcome

Timeframe: Events through 13 years of follow-up or through December 31, 2009; median follow-up 11.9 years.

Deaths from all causes were compared between the ovarian cancer screening arm and the usual care arm.

Outcome measures

Measure	Control n=34304 Participants Participants receive standard medical care.	Ovarian Screening n=34253 Participants Participants undergo blood sample collection for CA-125 analysis at baseline annually for 5 years. Participants also undergo an OVR (discontinued in December 1998) and TVU at baseline and annually for 3 years.
Deaths From All Causes	3542 Participants	3508 Participants

SECONDARY outcome

Timeframe: Events through 13 years of follow-up or through December 31, 2009; median follow-up 11.9 years.

Population: Female participants, excluding females without ovaries at baseline, were analyzed. An intention-to-treat analysis was performed.

Deaths from all causes were compared between the ovarian cancer screening arm and the usual care arm. Rate is the number of deaths divided by person years of follow-up in the study.

Outcome measures

Measure	Control n=34304 Participants Participants receive standard medical care.	Ovarian Screening n=34253 Participants Participants undergo blood sample collection for CA-125 analysis at baseline annually for 5 years. Participants also undergo an OVR (discontinued in December 1998) and TVU at baseline and annually for 3 years.
Death Rates From All Causes	92.6 Deaths per 10,000 PY	91.9 Deaths per 10,000 PY

SECONDARY outcome

Timeframe: Events through 13 years of follow-up or through December 31, 2009; median follow-up 11.9 years.

Population: Female participants, excluding females without ovaries at baseline, were analyzed. An intention-to-treat analysis was performed.

Ovarian cancer diagnoses confirmed by medical record abstraction.

Outcome measures

Measure	Control n=34304 Participants Participants receive standard medical care.	Ovarian Screening n=34253 Participants Participants undergo blood sample collection for CA-125 analysis at baseline annually for 5 years. Participants also undergo an OVR (discontinued in December 1998) and TVU at baseline and annually for 3 years.
Ovarian Cancer Incidence (Including Primary Peritoneal and Fallopian Tube Cancers)	176 Participants	212 Participants

SECONDARY outcome

Timeframe: Events through 13 years of follow-up or through December 31, 2009; median follow-up 11.9 years.

Population: Female participants, excluding females without ovaries at baseline, were analyzed. An intention-to-treat analysis was performed.

Ovarian cancer diagnoses confirmed by medical record abstraction. Incidence rate (cumulative) defined as ovarian cancer diagnoses divided by person years at risk for ovarian cancer.

Outcome measures

Measure	Control n=34304 Participants Participants receive standard medical care.	Ovarian Screening n=34253 Participants Participants undergo blood sample collection for CA-125 analysis at baseline annually for 5 years. Participants also undergo an OVR (discontinued in December 1998) and TVU at baseline and annually for 3 years.
Ovarian Cancer Incidence Rates (Including Primary Peritoneal and Fallopian Tube Cancers).	4.7 Diagnoses per 10,000 PY	5.7 Diagnoses per 10,000 PY

SECONDARY outcome

Timeframe: One year from screening examination

Population: The units analyzed were positive screening exams with documented diagnostic follow-up. If a participant received 3 positive screens with documented follow-up after each one, she would be counted 3 times in the number of units analyzed.

Number of positive screens with complications

Outcome measures

Measure	Control n=5970 Positive Screens with Follow-up Participants receive standard medical care.	Ovarian Screening Participants undergo blood sample collection for CA-125 analysis at baseline annually for 5 years. Participants also undergo an OVR (discontinued in December 1998) and TVU at baseline and annually for 3 years.
Complications of Diagnostic Evaluation (DE) Following a Positive Screening Test When DE Led to Ovarian Cancer Diagnosis	49 Positive screens w/ complications	—
Complications of Diagnostic Evaluation (DE) Following a Positive Screening Test When DE Did Not Lead to Ovarian Cancer Diagnosis	226 Positive screens w/ complications	—

SECONDARY outcome

Timeframe: T0 (at study entry)

Population: Females in the Ovarian Screening arm (excluding females with no ovaries at baseline) who had a CA-125 screen at T0 were analyzed.

Cancer Antigen 125 (CA-125) result.

Outcome measures

Measure	Control n=28733 Participants Participants receive standard medical care.	Ovarian Screening Participants undergo blood sample collection for CA-125 analysis at baseline annually for 5 years. Participants also undergo an OVR (discontinued in December 1998) and TVU at baseline and annually for 3 years.
T0 (Baseline) CA-125 Screening Results Positive (>= 35 U/mL)	400 Participants	—
T0 (Baseline) CA-125 Screening Results Inadequate screen	58 Participants	—
T0 (Baseline) CA-125 Screening Results Negative (<35 U/mL)	28275 Participants	—

SECONDARY outcome

Timeframe: T0 (at study entry)

Population: Females in the Ovarian Screening arm (excluding females with no ovaries at baseline) who had a TVU screen at T0 were analyzed.

Transvaginal Ultrasound (TVU) result.

Outcome measures

Measure	Control n=28477 Participants Participants receive standard medical care.	Ovarian Screening Participants undergo blood sample collection for CA-125 analysis at baseline annually for 5 years. Participants also undergo an OVR (discontinued in December 1998) and TVU at baseline and annually for 3 years.
T0 (Baseline) TVU Screening Results Negative	26624 Participants	—
T0 (Baseline) TVU Screening Results Positive	1309 Participants	—
T0 (Baseline) TVU Screening Results Inadequate screen	544 Participants	—

SECONDARY outcome

Timeframe: T1 (one year after entry)

Population: Females in the Ovarian Screening arm (excluding females with no ovaries at baseline) who had a CA-125 screen at T1 were analyzed.

Cancer Antigen 125 (CA-125) result.

Outcome measures

Measure	Control n=27514 Participants Participants receive standard medical care.	Ovarian Screening Participants undergo blood sample collection for CA-125 analysis at baseline annually for 5 years. Participants also undergo an OVR (discontinued in December 1998) and TVU at baseline and annually for 3 years.
T1 CA-125 Screening Results Negative (<35 U/mL)	27035 Participants	—
T1 CA-125 Screening Results Positive (>= 35 U/mL)	433 Participants	—
T1 CA-125 Screening Results Inadequate screen	46 Participants	—

SECONDARY outcome

Timeframe: T1 (one year after entry)

Population: Females in the Ovarian Screening arm (excluding females with no ovaries at baseline) who had a TVU screen at T1 were analyzed.

Transvaginal Ultrasound (TVU) result.

Outcome measures

Measure	Control n=27046 Participants Participants receive standard medical care.	Ovarian Screening Participants undergo blood sample collection for CA-125 analysis at baseline annually for 5 years. Participants also undergo an OVR (discontinued in December 1998) and TVU at baseline and annually for 3 years.
T1 TVU Screening Results Positive	930 Participants	—
T1 TVU Screening Results Negative	25740 Participants	—
T1 TVU Screening Results Inadequate screen	376 Participants	—

SECONDARY outcome

Timeframe: T2 (two years after entry)

Population: Females in the Ovarian Screening arm (excluding females with no ovaries at baseline) who had a CA-125 screen at T2 were analyzed.

Cancer Antigen 125 (CA-125) result.

Outcome measures

Measure	Control n=26555 Participants Participants receive standard medical care.	Ovarian Screening Participants undergo blood sample collection for CA-125 analysis at baseline annually for 5 years. Participants also undergo an OVR (discontinued in December 1998) and TVU at baseline and annually for 3 years.
T2 CA-125 Screening Results Negative (<35 U/mL)	26024 Participants	—
T2 CA-125 Screening Results Positive (>= 35 U/mL)	480 Participants	—
T2 CA-125 Screening Results Inadequate screen	51 Participants	—

SECONDARY outcome

Timeframe: T2 (one year after entry)

Population: Females in the Ovarian Screening arm (excluding females with no ovaries at baseline) who had a TVU screen at T2 were analyzed.

Transvaginal Ultrasound (TVU) result.

Outcome measures

Measure	Control n=26048 Participants Participants receive standard medical care.	Ovarian Screening Participants undergo blood sample collection for CA-125 analysis at baseline annually for 5 years. Participants also undergo an OVR (discontinued in December 1998) and TVU at baseline and annually for 3 years.
T2 TVU Screening Results Negative	24988 Participants	—
T2 TVU Screening Results Positive	764 Participants	—
T2 TVU Screening Results Inadequate screen	296 Participants	—

SECONDARY outcome

Timeframe: T3 (three years after entry)

Population: Females in the Ovarian Screening arm (excluding females with no ovaries at baseline) who had a CA-125 screen at T3 were analyzed.

Cancer Antigen 125 (CA-125) result.

Outcome measures

Measure	Control n=25401 Participants Participants receive standard medical care.	Ovarian Screening Participants undergo blood sample collection for CA-125 analysis at baseline annually for 5 years. Participants also undergo an OVR (discontinued in December 1998) and TVU at baseline and annually for 3 years.
T3 CA-125 Screening Results Negative (<35 U/mL)	24925 Participants	—
T3 CA-125 Screening Results Positive (>= 35 U/mL)	427 Participants	—
T3 CA-125 Screening Results Inadequate screen	49 Participants	—

SECONDARY outcome

Timeframe: T3 (three years after entry)

Population: Females in the Ovarian Screening arm (excluding females with no ovaries at baseline) who had a TVU screen at T3 were analyzed.

Transvaginal Ultrasound (TVU) result.

Outcome measures

Measure	Control n=24949 Participants Participants receive standard medical care.	Ovarian Screening Participants undergo blood sample collection for CA-125 analysis at baseline annually for 5 years. Participants also undergo an OVR (discontinued in December 1998) and TVU at baseline and annually for 3 years.
T3 TVU Screening Results Negative	23926 Participants	—
T3 TVU Screening Results Positive	733 Participants	—
T3 TVU Screening Results Inadequate screen	290 Participants	—

SECONDARY outcome

Timeframe: T4 (four years after entry)

Population: Females in the Ovarian Screening arm (excluding females with no ovaries at baseline) who had a CA-125 screen at T4 were analyzed.

Cancer Antigen 125 (CA-125) result.

Outcome measures

Measure	Control n=20115 Participants Participants receive standard medical care.	Ovarian Screening Participants undergo blood sample collection for CA-125 analysis at baseline annually for 5 years. Participants also undergo an OVR (discontinued in December 1998) and TVU at baseline and annually for 3 years.
T4 CA-125 Screening Results Positive (>= 35 U/mL)	327 Participants	—
T4 CA-125 Screening Results Inadequate screen	16 Participants	—
T4 CA-125 Screening Results Negative (<35 U/mL)	19772 Participants	—

SECONDARY outcome

Timeframe: T5 (five years after entry)

Population: Females in the Ovarian Screening arm (excluding females with no ovaries at baseline) who had a CA-125 screen at T5 were analyzed.

Cancer Antigen 125 (CA-125) result.

Outcome measures

Measure	Control n=22193 Participants Participants receive standard medical care.	Ovarian Screening Participants undergo blood sample collection for CA-125 analysis at baseline annually for 5 years. Participants also undergo an OVR (discontinued in December 1998) and TVU at baseline and annually for 3 years.
T5 CA-125 Screening Results Negative (<35 U/mL)	21788 Participants	—
T5 CA-125 Screening Results Positive (>= 35 U/mL)	366 Participants	—
T5 CA-125 Screening Results Inadequate screen	39 Participants	—

Adverse Events

Ovarian Screening

Serious events: 0 serious events

Other events: 903 other events

Deaths: 0 deaths

Serious adverse events

Adverse event data not reported

Other adverse events

Measure	Ovarian Screening n=34253 participants at risk Participants undergo blood sample collection for CA125 analysis at baseline annually for 5 years. Participants also undergo an OVR (discontinued in December 1998) and TVU at baseline and annually for 3 years.
General disorders Anxiety	0.01% 3/34253 • Number of events 3 • During each annual screening visit. These events are solely those prompted by the screening examination.
General disorders Bleeding	0.08% 26/34253 • Number of events 27 • During each annual screening visit. These events are solely those prompted by the screening examination.
General disorders Dizzy	0.23% 80/34253 • Number of events 82 • During each annual screening visit. These events are solely those prompted by the screening examination.
General disorders Fainted	0.08% 29/34253 • Number of events 31 • During each annual screening visit. These events are solely those prompted by the screening examination.
General disorders Inflammation	0.01% 2/34253 • Number of events 2 • During each annual screening visit. These events are solely those prompted by the screening examination.
General disorders Nausea	0.01% 4/34253 • Number of events 4 • During each annual screening visit. These events are solely those prompted by the screening examination.
General disorders Pain	0.08% 26/34253 • Number of events 26 • During each annual screening visit. These events are solely those prompted by the screening examination.
General disorders Bruising	1.3% 446/34253 • Number of events 453 • During each annual screening visit. These events are solely those prompted by the screening examination.
General disorders Hematoma	0.83% 284/34253 • Number of events 292 • During each annual screening visit. These events are solely those prompted by the screening examination.
General disorders Other Adverse Event	0.01% 3/34253 • Number of events 3 • During each annual screening visit. These events are solely those prompted by the screening examination.

Additional Information

Paul F. Pinsky, Ph.D.

Early Detection Research Group, NCI, NIH

Phone: 301-496-8544

Email: pinskyp@mail.nih.gov

Results disclosure agreements

• Principal investigator is a sponsor employee
• Publication restrictions are in place

Restriction type: LTE60